Intel DQ77KB: A Low Power LGA1155 Motherboard

As the DQ77KB uses an external DC power source we compared its power consumption to a group of mini PCs with varying levels of CPU power. The processors used in this comparison group range from the relatively slow Atom N2600 to the formidable quad core Core i5-2500S. The CPU we paired with the DQ77KB is an Ivy Bridge part, the 55W dual core Pentium G2120 which runs at 3.1 GHz.

*Figures for the M91 were adjusted downward from our original test run to account for its less efficient desktop hard drive (notebook hard drives and SSDs were used with the other systems compared).

Note: that all the systems above were tested with different power supplies of varying efficiency, so consider these numbers a rough comparison.

In light load situations (idle and playing H.264 video), our system used less than 20W which is higher than most of the nettops we've recently reviewed. However, considering it was equipped with an off-the-shelf desktop processor running at more than 3 GHz, it's an impressive result, though not unprecedented. The Lenovo ThinkCentre M91p SFF PC we examined last year came very close in idle draw. The M91p had similar hardware including a a laptop-style motherboard with SO-DIMM memory, and a hefty DC power brick, though it was armed with the much more capable Core i5-2500S, a 65W part. It's also important to note that while these figure are promising, they still don't hold a candle to real mobile hardware like the internals of the Intel NUC DC3217BY. The NUC idles at just 10W or 40% less than the DQ77KB/G2120.

Its efficiency on heavy load was more of an eye-opener, just 41W with the CPU stressed to its theoretical limit, and 56W total with the GPU thrown into the mix as well. It's especially surprising considering the Pentium G2120's rated TDP is 55W and that our numbers are in AC, not accounting for the inefficiency of the power supply. For an entire system to draw that much for the wall is simply amazing. This is probably more of a compliment to the CPU rather than the board however.

On load, the Pentium G2120 was pulling under 1.000 V according to CPU-Z. This undoubtedly contributed to the DQ77KB's excellent power draw figures.

SATA Performance

As the DQ77KB uses the same native SATA controller as the rest of Intel's 7 series, it's a known quantity. It scores very well in CrystalDiskMark, eclipsing AMD's latest controllers in almost every test and is especially dominant in big block writes with large deep queues, an operation frequently used on servers with multi-user access.

USB 3.0 Performance

Our experience with Intel's native USB 3.0 controller is less reliable, with the odd board sometimes mysteriously producing poor results despite using the same hardware. In the DQ77KB's case, USB 3.0 performance was on target aside from a slight slow down in large block writes.